Baking oven



Dec. 23, 1930. c. A. WYMAN 1,786,142

BAKING OVEN Filed May 10, 1927 2 Sheets-Sheet 1 p; A; I .NVENTOR" 4 6r/w 0. #21212 49 45 4a v ATTORNEY Dec. 23, 1930. c, WYMAN 1,786,142

BAKING OVEN Filed May 10, 1927.

-2 Sheets-Sheet 2 INVENTOR BY &4 W ATTORNEY Patented Dec. 23, 1930UNITED STATES PATENTLOFF'ICE BAKING OVEN.

Application filed May 10, 1927. Serial No. 190,197.

This invention relates to ovens for use in bakeries, hotels and otherplaces where large quantities of bread or other kinds of food are to becooked.

a The object of the invention is the provision of an oven of thischaracter whereby bread and other comestibles may be cooked moreuniformly, expeditiously and conveniently than hitherto.

Another object of the invention is to provide for these purposes asimple, compact oven structure which is inexpensive to oper ate both asto fuel and labor.

Another object is to provide an oven which 15 is readily kept clean andin good working condition.

To these and other ends which will appear in the followingspecification, the invention consists in the novel construction,adaptation 20 and combination of parts hereinafter described andclaimed.

In the accompanying drawings,

Figure 1 is a horizontal sectional View through 11 of Fig. 2 of an ovenembodying the present invention, parts being broken away. Fig. 2 is avertical section taken substantially on line 22 of Fig. 1. Fig. 3

is a fragmentary top plan view of the oven structure, to illustrate thenow preferred manner of drivingthe rotary cage, which is shown in thepreceding views. Fig. l is a detail vertical section on line l4 ofFig. 1. Fig. 5 is a perspective view of one of the parts of a floorbox-element of a rotary shelf. Fig. 6 is a longitudinal vertical sectionof a floor box-member.

In said drawings, the reference numeral 10 represents the base portionof the oven structure which is desirably circular in horizontal sectionand supports the circular peripheral wall 11 of the oven chamber 12 andits roof 13.

Said oven structure is of brick, concrete or other material able towithstand the heat employed in the device, and which is a relativelypoor heat conductor.

Provided in the oven base is a chamber which is divided by a grate 14:to provide a furnace chamber 15 and an ash pit 16 above and below thegrate, respectively. In the upper portion of the oven base 10 andseparated by means of metal plates 10 from the oven chamber 12 is anannular channel17 connecting the furnace chamber by two semi-circularfiues withlthe lower end of an upwardly extending fine 18 atdiametrically opposite sides of the oven from the furnace.

The upper end of the riser flue 18 is connected by means of twosemi-circular lines such as 19,'with a chimney inlet 20 above thefurnace. 21 and 22 are cleanout openings for the horizontal lines 17 and19, respectively, the same being provided with removable closures21 and22 The ceiling of the oven chamber 12 constitutes the floors of theflues 19, said ceiling being made of relatively thin brickwork 23 overmetal plates 2 1 supported by girder elements 25. The covering of therelatively quick heat-conducting plates 24-by' the thin brickworkprevents a rapid cooling of the oven chamber from above in the event 7of any abatement or extinguishing of the fire, I yet permits heatpassing down by conduction into the oven chamber from hot smoke orburning combustible gases passing through the flues 19 to the chimney.The ceiling of the flues 19 are advantageously protected by a poor heatconducting material or materials which are supported upon iron plates26; as, for example, layers 27 and 28, respectively, of sheet asbestosand sand, and above which is brick work 29.

Extendingaxially through said structure is a vertical shaft consisting,preferably, of a length of pipe 30 rigidly connected by a coupling 31with a shaft element 32.

The shaft part extends through a tubular bearing 33 in the structureabove the oven chamber the pipe part of the shaft extending througha'tubular bearing 34; in the structure into a compartment 36 below theoven chamber.

The lower end of the shaft is provided with a circular foot piece 37which is desirably mounted upon hearing balls 38 provided in V thecavity of a supporting plate 39.

Above the oven structure, said shaft has mounted thereon a worm wheel 10which is driven by a worm 11 upon a counter shaft 42 (Fig. 3) which isjournaled in suitable bearing boxes as 13.

As shown, the shaft 42 has mounted thereon a friction wheel 4% which isdriven by means of a friction pinion 45 upon another shaft "-6 which isjournalcd in the free end of a frame 47. This frame is pivotallyconnected at its other end to bosses 48 of bearing boxes tlof a powerdriven shaft 50;

51 represents an endless transmission belt passin about pulleys 50 andQ6 upon the espective shafts 50 and 46 to effect the rota.- tion of thepinion which contacts peripherally with the friction wheel 4. 1. Asillustrated the frame 457 is arranged to have its free end supported bythe wheel l4: to ensure sufficient weight for friction between saidwheel and pinion for driving the rotary parts in the even chamber.

T he shaft 50 may be driven by any suitable power means, such forinstance, as an electri c motor which is denoted by M.

Rigidly secured to the part- 30 of the vertical shaft within the ovenchamber is a cage consisting of vertically spaced apart skeletonrames,.two being shown in Fig. 2, which are denoted by 52 and 52respectively.

Each of these frames is composed of a plurality of radially disposedbars 53 connected to circumferentially arranged bar elements and havinghorizontal flange elements 54 ans. The bar flanges 54 and 55 furnishseats for supporting the ends of boxes 56 containing asbestos 57 (Fig.6) or other heat retarding material. The boxes are preferably formed oftwo complementary parts 56 (one being shown in Fig. 5) which are coupledtogether as by means of bolts 58.

Depending from. the lower frame 52 is a plurality of vanes 59 whichfunction to effect acirculatory movement of the heated air beneath said.frame. The floor boxes 56 areeniployed' in the various spaces providedtherefor by the. respectivebars 53,- 5 l and 55 of said skeleton frames52 and 52 thereby pro,- vicing substantially continuous annularplatforms or shelves disposed in horizontal planes one above the other;The food which isto be cooked in the oven is placed in pans, orotherwise, upon either of said platforms and is revolved withthe latterin an orbital path about the interior of the oven chamber until thecooking is completed.

The foodin its raw state inserted into the oven chamber through openings60 and 60 for the respective platforms;

The doors 60 for the oven openings are representedin F l, one beingclosed, the other open and supported bracketelike by means of an arm61engageable with the oven all.

The rotation of-the circular platforms with the articles to be cookedand, the vanes 59 depending from the frame of the lower platform, servesto circulate the heated air with in the oven chamber for cookingpurposes.

In the baking of some kinds of comestibles, a more rapid movement of theheated air is desirable as, for example, in crusting certain kinds ofbread loaves. To which end, I provide means to create hot air currentswhich will traverse the rotating shelves diametrically of the oven.

Such means comprises one or more rotary fans, two being shown, which areindicated by ($2 and 63, the same being located to rotate abouthorizontal axes disposed slightly above the planes of the respectiveshelves. The fans may be driven by means of individual electric motors62 and 63 through the medium of "heir armature shafts which extendthrough the oven wall 11 from the motors at the outside to the fanswithin the oven. These fans are, moreover, lo 'ated in ducts 62 and 63each having a discharge opening-as 6l-in front of the respective duct,and receiving hot air from the space between the plate 1.0 which isdirectly above the furna 'e chambe f and a battle plate (35.

The partition 66 between the ducts (i2 and 63 extends as flange 66 belowthe ballle plate. Cther flanges similar to (56- and indicated by dottedlines 67 in Fig. 1, are provided along the side edges of the baliie toprovide channels extending radially of the oven center, between thebaffle and the hot plates 10 which are above the furnace to the ducts ofthe respective fans.

A damper valve, represented by 69 in Fig. 2, is provided in'theperipheral wall of the oven chamber for controlling the effective sizeof an opening making communication between the oven chamber 12. and theuptake smoke flue 18,.for the purpose of witl'idrawing heated air andcooking fumes from the oven chamber into the referred to flue. Theregulating of the damper valve may be attained by means of a rodinserted through the clean-out opening 21.

In operation, the smoke and hot combustion produced in the furnace passupwardly from the latter into the tlues 17 whence they pass upwardlythrough the flue 18 to escape through fines 19 into the chimneyconnection 20. In thus passing through the fines 17, and 19, the greaterportion of the heat contained in the combustion gases, etc., isconducted through the plates 1(" and 24 into the oven-chamber 12.

The relatively great heat radiated from those of the plates 10 which aredirectly above the furnace isintercepted by the battle 65 and is drawnfrom the space below the battle through ducts 62 and by means of fans 62and (S3 to be delivered in streams of air driven substantiallydiametrically across the oven chamber to subject the broader otherarticles of food which are carried upon the shelves to a top heat assuch articles successively pass through such hot air streams;

The use of the vanes 59 in imparting a circulatory movement to the airabove all of the plates 10 is an important feature of the invention byreason of their functioning to equalize the heat, and enable the bakingto be eflectually performed in all parts of the oven chamber.

In the event that it is desirable that the temperature of the interiorof the oven chamber should, for any reason, be lowered, the damper 69 ismoved into its open position, whereupon the draft obtaining in the flue18 serves to suck the air from the oven. chamber. When the damper 69 isthus utilized the vanes 59, one or the other of the doors (50 should beopened more or less for the admission of relatively cool air from theoutside to replace the hot air withdrawn from the inside of the ovenchamber. 7 1

From the foregoing description it is believed that the construction andoperation of the illustrated embodiment of the invention will beunderstood.

While I have described with much detail an embodiment of the inventionnow preferred by me, I do not wish to confine myself specificallythereto except as limited by the scope of the appended claims.

What I claim, is

1. In a baking oven of the character described, having a baking chamber,a furnace located below the chamber, a metal wall located' above thefurnace and serving to partition the latter from said chamber, a rotaryshelf provided in the chamber and'adapted to revolve about said wall, ahorizontal baffle located between said wall and the rotary shelf, a fanlocated at one side of the cham-' her, a conduit extending from thespace between said wall and the baflie to the fan, and means to drivethe fan to effect the withdrawal of hot air from said space and its'delivery diametrically of the chamber and above the shelf.

2. In a baking oven, the combination with the casing having a circularchamber, heat.

conducting flues in the floor and ceiling walls of said chamber, avertical shaft extending axially through said chamber, annularhorizontal shelves carried by said shaft, a furnace provided in thecasing wall beneath said chamber at one side of the latter, said furnacehaving communicative connection with said fines, and vanes provided insaid chamber and revolubly carried by the shaft to pass successivelythrough the relatively hot portion therein above the furnace and effecta horizontal circulatory movement of the heated air for distributing theheat uniformly in the chamber.

3. In a baking oven of the character described, the combination of thecasing containing a circular oven chamber, a cage pro-. vided in saidchamber and rotatable about the vertical axis thereof, power drivenmeans for rotating the cage, shelf devices removably mounted upon saidcage, said devices being arranged to provide a plurality of annular bythe shaft, a horizontally disposed fan member comprising verticallyarranged blades secured to the shaft, and a power operated means forrotating the shaft to revolve said blades to effect the horizontalcirculation of heated air in the oven.

5. In a baking oven, an inclosed baking chamber, a flue exteriorlydisposed with respect to said chamber beneath the floor thereof, saidflue being arranged to conduct heated air from a furnace, and a powerdriven fan within said chamber, said fan being arranged to force heatedair transversely of said cham ber on a'horizontal plane substantiallymidway of the height thereof, said fan being cooperative with meansincluding a horizontally disposed bafiie for trapping the air adjacentsaid flue-heated floor for conducting the same to the fan.

Signed at Seattle, WVashington, this l lth day of April, 1927.

CHARLES A. VVYMAN.

